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1. The Relationship Between Maturation Size and Maximum Tree Size From Tropical to Boreal Climates

Author

Journé, Valentin, Bogdziewicz, Michał, Courbaud, Benoit, Kunstler, Georges, Qiu, Tong, Acuña, Marie‐Claire Aravena, Ascoli, Davide, Bergeron, Yves, Berveiller, Daniel, Boivin, Thomas, Bonal, Raul, Caignard, Thomas, Cailleret, Maxime, Calama, Rafael, Camarero, J Julio, Chang‐Yang, Chia‐Hao, Chave, Jerome, Chianucci, Francesco, Curt, Thomas, Cutini, Andrea, Das, Adrian, Daskalakou, Evangelia, Davi, Hendrik, Delpierre, Nicolas, Delzon, Sylvain, Dietze, Michael, Calderon, Sergio Donoso, Dormont, Laurent, Espelta, Josep Maria, Farfan‐Rios, William, Fenner, Michael, Franklin, Jerry, Gehring, Catherine, Gilbert, Gregory, Gratzer, Georg, Greenberg, Cathryn H, Guignabert, Arthur, Guo, Qinfeng, Hacket‐Pain, Andrew, Hampe, Arndt, Han, Qingmin, Hanley, Mick E, Lambers, Janneke Hille Ris, Holík, Jan, Hoshizaki, Kazuhiko, Ibanez, Ines, Johnstone, Jill F, Knops, Johannes MH, Kobe, Richard K, Kurokawa, Hiroko, Lageard, Jonathan, LaMontagne, Jalene, Ledwon, Mateusz, Lefèvre, François, Leininger, Theodor, Limousin, Jean‐Marc, Lutz, James, Macias, Diana, Mårell, Anders, McIntire, Eliot, Moran, Emily V, Motta, Renzo, Myers, Jonathan, Nagel, Thomas A, Naoe, Shoji, Noguchi, Mahoko, Norghauer, Julian, Oguro, Michio, Ourcival, Jean‐Marc, Parmenter, Robert, Pearse, Ian, Pérez‐Ramos, Ignacio M, Piechnik, Łukasz, Podgórski, Tomasz, Poulsen, John, Redmond, Miranda D, Reid, Chantal D, Samonil, Pavel, Scher, C Lane, Schlesinger, William H, Seget, Barbara, Sharma, Shubhi, Shibata, Mitsue, Silman, Miles, Steele, Michael, Stephenson, Nathan, Straub, Jacob, Sutton, Samantha, Swenson, Jennifer J, Swift, Margaret, Thomas, Peter A, Uriarte, Maria, Vacchiano, Giorgio, Whipple, Amy, Whitham, Thomas, Wright, S Joseph, Zhu, Kai, Zimmerman, Jess, Żywiec, Magdalena, and Clark, James S

Subjects
Biological Sciences, Ecology, Trees, Tropical Climate, Climate Change, Reproduction, Forests, allometry, life history, seed production, size, tree fecundity, tree maturation, Ecological Applications, Evolutionary Biology, Ecological applications, Environmental management
Abstract

The fundamental trade-off between current and future reproduction has long been considered to result in a tendency for species that can grow large to begin reproduction at a larger size. Due to the prolonged time required to reach maturity, estimates of tree maturation size remain very rare and we lack a global view on the generality and the shape of this trade-off. Using seed production from five continents, we estimate tree maturation sizes for 486 tree species spanning tropical to boreal climates. Results show that a species' maturation size increases with maximum size, but in a non-proportional way: the largest species begin reproduction at smaller sizes than would be expected if maturation were simply proportional to maximum size. Furthermore, the decrease in relative maturation size is steepest in cold climates. These findings on maturation size drivers are key to accurately represent forests' responses to disturbance and climate change.

Published
2024

2. Advancing Marine Arctic Science through Facilitating International Collaborations

Author

Weijer, Wilbert, Veneziani, Milena, Kinney, Jaclyn Clement, Maslowski, Wieslaw, Zhang, Jiaxu, and Steele, Michael

Subjects
Marine sciences -- Research, Arctic research -- Conferences, meetings and seminars, Business, Earth sciences
Abstract

KEYWORDS: Ocean; Arctic; Sea ice; Ocean dynamics; Small scale processes; Atmosphere-ocean interaction Inaugural Workshop and Early Career School of the Consortium for the Advancement of Marine Arctic Science (CAMAS) What: [...]

Published
2024
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5. Linking seed size and number to trait syndromes in trees

Author

Bogdziewicz, Michal, Acuña, Marie‐Claire Aravena, Andrus, Robert, Ascoli, Davide, Bergeron, Yves, Brveiller, Daniel, Boivin, Thomas, Bonal, Raul, Caignard, Thomas, Cailleret, Maxime, Calama, Rafael, Calderon, Sergio Donoso, Camarero, J Julio, Chang‐Yang, Chia‐Hao, Chave, Jerome, Chianucci, Francesco, Cleavitt, Natalie L, Courbaud, Benoit, Cutini, Andrea, Curt, Thomas, Das, Adrian J, Davi, Hendrik, Delpierre, Nicolas, Delzon, Sylvain, Dietze, Michael, Dormont, Laurent, Farfan‐Rios, William, Gehring, Catherine A, Gilbert, Gregory S, Gratzer, Georg, Greenberg, Cathryn H, Guignabert, Arthur, Guo, Qinfeng, Hacket‐Pain, Andrew, Hampe, Arndt, Han, Qingmin, Hoshizaki, Kazuhiko, Ibanez, Ines, Johnstone, Jill F, Journé, Valentin, Kitzberger, Thomas, Knops, Johannes MH, Kunstler, Georges, Kobe, Richard, Lageard, Jonathan GA, LaMontagne, Jalene M, Ledwon, Mateusz, Leininger, Theodor, Limousin, Jean‐Marc, Lutz, James A, Macias, Diana, Marell, Anders, McIntire, Eliot JB, Moran, Emily, Motta, Renzo, Myers, Jonathan A, Nagel, Thomas A, Naoe, Shoji, Noguchi, Mahoko, Oguro, Michio, Kurokawa, Hiroko, Ourcival, Jean‐Marc, Parmenter, Robert, Perez‐Ramos, Ignacio M, Piechnik, Lukasz, Podgórski, Tomasz, Poulsen, John, Qiu, Tong, Redmond, Miranda D, Reid, Chantal D, Rodman, Kyle C, Šamonil, Pavel, Holik, Jan, Scher, C Lane, Van Marle, Harald Schmidt, Seget, Barbara, Shibata, Mitsue, Sharma, Shubhi, Silman, Miles, Steele, Michael A, Straub, Jacob N, Sun, I‐Fang, Sutton, Samantha, Swenson, Jennifer J, Thomas, Peter A, Uriarte, Maria, Vacchiano, Giorgio, Veblen, Thomas T, Wright, Boyd, Wright, S Joseph, Whitham, Thomas G, Zhu, Kai, Zimmerman, Jess K, Zywiec, Magdalna, and Clark, James S

Subjects
fecundity, functional traits, leaf economics, life history strategies, size syndrome, tree recruitment, Ecology
Published
2023

9. Globally, tree fecundity exceeds productivity gradients

Author

Journé, Valentin, Andrus, Robert, Aravena, Marie‐Claire, Ascoli, Davide, Berretti, Roberta, Berveiller, Daniel, Bogdziewicz, Michal, Boivin, Thomas, Bonal, Raul, Caignard, Thomas, Calama, Rafael, Camarero, Jesús Julio, Chang‐Yang, Chia‐Hao, Courbaud, Benoit, Courbet, Francois, Curt, Thomas, Das, Adrian J, Daskalakou, Evangelia, Davi, Hendrik, Delpierre, Nicolas, Delzon, Sylvain, Dietze, Michael, Calderon, Sergio Donoso, Dormont, Laurent, Espelta, Josep Maria, Fahey, Timothy J, Farfan‐Rios, William, Gehring, Catherine A, Gilbert, Gregory S, Gratzer, Georg, Greenberg, Cathryn H, Guo, Qinfeng, Hacket‐Pain, Andrew, Hampe, Arndt, Han, Qingmin, Lambers, Janneke Hille Ris, Hoshizaki, Kazuhiko, Ibanez, Ines, Johnstone, Jill F, Kabeya, Daisuke, Kays, Roland, Kitzberger, Thomas, Knops, Johannes MH, Kobe, Richard K, Kunstler, Georges, Lageard, Jonathan GA, LaMontagne, Jalene M, Leininger, Theodor, Limousin, Jean‐Marc, Lutz, James A, Macias, Diana, McIntire, Eliot JB, Moore, Christopher M, Moran, Emily, Motta, Renzo, Myers, Jonathan A, Nagel, Thomas A, Noguchi, Kyotaro, Ourcival, Jean‐Marc, Parmenter, Robert, Pearse, Ian S, Perez‐Ramos, Ignacio M, Piechnik, Lukasz, Poulsen, John, Poulton‐Kamakura, Renata, Qiu, Tong, Redmond, Miranda D, Reid, Chantal D, Rodman, Kyle C, Rodriguez‐Sanchez, Francisco, Sanguinetti, Javier D, Scher, C Lane, Van Marle, Harald Schmidt, Seget, Barbara, Sharma, Shubhi, Silman, Miles, Steele, Michael A, Stephenson, Nathan L, Straub, Jacob N, Swenson, Jennifer J, Swift, Margaret, Thomas, Peter A, Uriarte, Maria, Vacchiano, Giorgio, Veblen, Thomas T, Whipple, Amy V, Whitham, Thomas G, Wright, Boyd, Wright, S Joseph, Zhu, Kai, Zimmerman, Jess K, Zlotin, Roman, Zywiec, Magdalena, and Clark, James S

Subjects
Climate Change Impacts and Adaptation, Biological Sciences, Ecology, Environmental Sciences, Regenerative Medicine, Biodiversity, Climate, Fertility, Forests, Seeds, Trees, climate, competition, forest regeneration, seed consumption, species interactions, tree fecundity, Ecological Applications, Evolutionary Biology, Ecological applications, Environmental management
Abstract

Lack of tree fecundity data across climatic gradients precludes the analysis of how seed supply contributes to global variation in forest regeneration and biotic interactions responsible for biodiversity. A global synthesis of raw seedproduction data shows a 250-fold increase in seed abundance from cold-dry to warm-wet climates, driven primarily by a 100-fold increase in seed production for a given tree size. The modest (threefold) increase in forest productivity across the same climate gradient cannot explain the magnitudes of these trends. The increase in seeds per tree can arise from adaptive evolution driven by intense species interactions or from the direct effects of a warm, moist climate on tree fecundity. Either way, the massive differences in seed supply ramify through food webs potentially explaining a disproportionate role for species interactions in the wet tropics.

Published
2022

10. North American tree migration paced by climate in the West, lagging in the East

Author

Sharma, Shubhi, Andrus, Robert, Bergeron, Yves, Bogdziewicz, Michal, Bragg, Don C, Brockway, Dale, Cleavitt, Natalie L, Courbaud, Benoit, Das, Adrian J, Dietze, Michael, Fahey, Timothy J, Franklin, Jerry F, Gilbert, Gregory S, Greenberg, Cathryn H, Guo, Qinfeng, Lambers, Janneke Hille Ris, Ibanez, Ines, Johnstone, Jill F, Kilner, Christopher L, Knops, Johannes MH, Koenig, Walter D, Kunstler, Georges, LaMontagne, Jalene M, Macias, Diana, Moran, Emily, Myers, Jonathan A, Parmenter, Robert, Pearse, Ian S, Poulton-Kamakura, Renata, Redmond, Miranda D, Reid, Chantal D, Rodman, Kyle C, Scher, C Lane, Schlesinger, William H, Steele, Michael A, Stephenson, Nathan L, Swenson, Jennifer J, Swift, Margaret, Veblen, Thomas T, Whipple, Amy V, Whitham, Thomas G, Wion, Andreas P, Woodall, Christopher W, Zlotin, Roman, and Clark, James S

Subjects
Climate Action, Climate Change, Ecosystem, Fertility, Geography, North America, Trees, Uncertainty, climate change, forest regeneration, seed production, tree migration
Abstract

Tree fecundity and recruitment have not yet been quantified at scales needed to anticipate biogeographic shifts in response to climate change. By separating their responses, this study shows coherence across species and communities, offering the strongest support to date that migration is in progress with regional limitations on rates. The southeastern continent emerges as a fecundity hotspot, but it is situated south of population centers where high seed production could contribute to poleward population spread. By contrast, seedling success is highest in the West and North, serving to partially offset limited seed production near poleward frontiers. The evidence of fecundity and recruitment control on tree migration can inform conservation planning for the expected long-term disequilibrium between climate and forest distribution.

Published
2022

11. Limits to reproduction and seed size-number trade-offs that shape forest dominance and future recovery

Author

Qiu, Tong, Andrus, Robert, Aravena, Marie-Claire, Ascoli, Davide, Bergeron, Yves, Berretti, Roberta, Berveiller, Daniel, Bogdziewicz, Michal, Boivin, Thomas, Bonal, Raul, Bragg, Don C, Caignard, Thomas, Calama, Rafael, Camarero, J Julio, Chang-Yang, Chia-Hao, Cleavitt, Natalie L, Courbaud, Benoit, Courbet, Francois, Curt, Thomas, Das, Adrian J, Daskalakou, Evangelia, Davi, Hendrik, Delpierre, Nicolas, Delzon, Sylvain, Dietze, Michael, Calderon, Sergio Donoso, Dormont, Laurent, Espelta, Josep, Fahey, Timothy J, Farfan-Rios, William, Gehring, Catherine A, Gilbert, Gregory S, Gratzer, Georg, Greenberg, Cathryn H, Guo, Qinfeng, Hacket-Pain, Andrew, Hampe, Arndt, Han, Qingmin, Hille Ris Lambers, Janneke, Hoshizaki, Kazuhiko, Ibanez, Ines, Johnstone, Jill F, Journé, Valentin, Kabeya, Daisuke, Kilner, Christopher L, Kitzberger, Thomas, Knops, Johannes MH, Kobe, Richard K, Kunstler, Georges, Lageard, Jonathan GA, LaMontagne, Jalene M, Ledwon, Mateusz, Lefevre, Francois, Leininger, Theodor, Limousin, Jean-Marc, Lutz, James A, Macias, Diana, McIntire, Eliot JB, Moore, Christopher M, Moran, Emily, Motta, Renzo, Myers, Jonathan A, Nagel, Thomas A, Noguchi, Kyotaro, Ourcival, Jean-Marc, Parmenter, Robert, Pearse, Ian S, Perez-Ramos, Ignacio M, Piechnik, Lukasz, Poulsen, John, Poulton-Kamakura, Renata, Redmond, Miranda D, Reid, Chantal D, Rodman, Kyle C, Rodriguez-Sanchez, Francisco, Sanguinetti, Javier D, Scher, C Lane, Schlesinger, William H, Schmidt Van Marle, Harald, Seget, Barbara, Sharma, Shubhi, Silman, Miles, Steele, Michael A, Stephenson, Nathan L, Straub, Jacob N, Sun, I-Fang, Sutton, Samantha, Swenson, Jennifer J, Swift, Margaret, Thomas, Peter A, Uriarte, Maria, Vacchiano, Giorgio, Veblen, Thomas T, Whipple, Amy V, Whitham, Thomas G, Wion, Andreas P, Wright, Boyd, Wright, S Joseph, Zhu, Kai, and Zimmerman, Jess K

Subjects
Agricultural, Veterinary and Food Sciences, Biological Sciences, Ecology, Contraception/Reproduction, Fertility, Forests, Reproduction, Seeds, Trees
Abstract

The relationships that control seed production in trees are fundamental to understanding the evolution of forest species and their capacity to recover from increasing losses to drought, fire, and harvest. A synthesis of fecundity data from 714 species worldwide allowed us to examine hypotheses that are central to quantifying reproduction, a foundation for assessing fitness in forest trees. Four major findings emerged. First, seed production is not constrained by a strict trade-off between seed size and numbers. Instead, seed numbers vary over ten orders of magnitude, with species that invest in large seeds producing more seeds than expected from the 1:1 trade-off. Second, gymnosperms have lower seed production than angiosperms, potentially due to their extra investments in protective woody cones. Third, nutrient-demanding species, indicated by high foliar phosphorus concentrations, have low seed production. Finally, sensitivity of individual species to soil fertility varies widely, limiting the response of community seed production to fertility gradients. In combination, these findings can inform models of forest response that need to incorporate reproductive potential.

Published
2022

12. Genomic investigations of unexplained acute hepatitis in children

Author

Morfopoulou, Sofia, Buddle, Sarah, Torres Montaguth, Oscar Enrique, Atkinson, Laura, Guerra-Assunção, José Afonso, Moradi Marjaneh, Mahdi, Zennezini Chiozzi, Riccardo, Storey, Nathaniel, Campos, Luis, Hutchinson, J. Ciaran, Counsell, John R., Pollara, Gabriele, Roy, Sunando, Venturini, Cristina, Antinao Diaz, Juan F., Siam, Ala’a, Tappouni, Luke J., Asgarian, Zeinab, Ng, Joanne, Hanlon, Killian S., Lennon, Alexander, McArdle, Andrew, Czap, Agata, Rosenheim, Joshua, Andrade, Catarina, Anderson, Glenn, Lee, Jack C. D., Williams, Rachel, Williams, Charlotte A., Tutill, Helena, Bayzid, Nadua, Martin Bernal, Luz Marina, Macpherson, Hannah, Montgomery, Kylie-Ann, Moore, Catherine, Templeton, Kate, Neill, Claire, Holden, Matt, Gunson, Rory, Shepherd, Samantha J., Shah, Priyen, Cooray, Samantha, Voice, Marie, Steele, Michael, Fink, Colin, Whittaker, Thomas E., Santilli, Giorgia, Gissen, Paul, Kaufer, Benedikt B., Reich, Jana, Andreani, Julien, Simmonds, Peter, Alrabiah, Dimah K., Castellano, Sergi, Chikowore, Primrose, Odam, Miranda, Rampling, Tommy, Houlihan, Catherine, Hoschler, Katja, Talts, Tiina, Celma, Cristina, Gonzalez, Suam, Gallagher, Eileen, Simmons, Ruth, Watson, Conall, Mandal, Sema, Zambon, Maria, Chand, Meera, Hatcher, James, De, Surjo, Baillie, Kenneth, Semple, Malcolm Gracie, Martin, Joanne, Ushiro-Lumb, Ines, Noursadeghi, Mahdad, Deheragoda, Maesha, Hadzic, Nedim, Grammatikopoulos, Tassos, Brown, Rachel, Kelgeri, Chayarani, Thalassinos, Konstantinos, Waddington, Simon N., Jacques, Thomas S., Thomson, Emma, Levin, Michael, Brown, Julianne R., and Breuer, Judith

Published
2023
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13. Continent-wide tree fecundity driven by indirect climate effects.

Author

Clark, James S, Andrus, Robert, Aubry-Kientz, Melaine, Bergeron, Yves, Bogdziewicz, Michal, Bragg, Don C, Brockway, Dale, Cleavitt, Natalie L, Cohen, Susan, Courbaud, Benoit, Daley, Robert, Das, Adrian J, Dietze, Michael, Fahey, Timothy J, Fer, Istem, Franklin, Jerry F, Gehring, Catherine A, Gilbert, Gregory S, Greenberg, Cathryn H, Guo, Qinfeng, HilleRisLambers, Janneke, Ibanez, Ines, Johnstone, Jill, Kilner, Christopher L, Knops, Johannes, Koenig, Walter D, Kunstler, Georges, LaMontagne, Jalene M, Legg, Kristin L, Luongo, Jordan, Lutz, James A, Macias, Diana, McIntire, Eliot JB, Messaoud, Yassine, Moore, Christopher M, Moran, Emily, Myers, Jonathan A, Myers, Orrin B, Nunez, Chase, Parmenter, Robert, Pearse, Sam, Pearson, Scott, Poulton-Kamakura, Renata, Ready, Ethan, Redmond, Miranda D, Reid, Chantal D, Rodman, Kyle C, Scher, C Lane, Schlesinger, William H, Schwantes, Amanda M, Shanahan, Erin, Sharma, Shubhi, Steele, Michael A, Stephenson, Nathan L, Sutton, Samantha, Swenson, Jennifer J, Swift, Margaret, Veblen, Thomas T, Whipple, Amy V, Whitham, Thomas G, Wion, Andreas P, Zhu, Kai, and Zlotin, Roman

Subjects
Trees, Seasons, Fertility, Geography, Models, Theoretical, North America, Climate Change, Models, Theoretical
Abstract

Indirect climate effects on tree fecundity that come through variation in size and growth (climate-condition interactions) are not currently part of models used to predict future forests. Trends in species abundances predicted from meta-analyses and species distribution models will be misleading if they depend on the conditions of individuals. Here we find from a synthesis of tree species in North America that climate-condition interactions dominate responses through two pathways, i) effects of growth that depend on climate, and ii) effects of climate that depend on tree size. Because tree fecundity first increases and then declines with size, climate change that stimulates growth promotes a shift of small trees to more fecund sizes, but the opposite can be true for large sizes. Change the depresses growth also affects fecundity. We find a biogeographic divide, with these interactions reducing fecundity in the West and increasing it in the East. Continental-scale responses of these forests are thus driven largely by indirect effects, recommending management for climate change that considers multiple demographic rates.

Published
2021

16. Does masting scale with plant size? High reproductive variability and low synchrony in small and unproductive individuals

Author

Bogdziewicz, Michał, Szymkowiak, Jakub, Calama, Rafael, Crone, Elizabeth E, Espelta, Josep M, Lesica, Peter, Marino, Shealyn, Steele, Michael A, Tenhumberg, Brigitte, Tyre, Andrew, Żywiec, Magdalena, and Kelly, Dave

Subjects
Plant Biology, Biological Sciences, Ecology, Humans, Pinus, Quercus, Reproduction, Seeds, Sorbus, Fecundity, mast seeding, plant reproduction, predator satiation, seed predation, super-producers, Forestry Sciences, Plant Biology & Botany, Plant biology
Abstract

Background and aimsIn a range of plant species, the distribution of individual mean fecundity is skewed and dominated by a few highly fecund individuals. Larger plants produce greater seed crops, but the exact nature of the relationship between size and reproductive patterns is poorly understood. This is especially clear in plants that reproduce by exhibiting synchronized quasi-periodic variation in fruit production, a process called masting.MethodsWe investigated covariation of plant size and fecundity with individual-plant-level masting patterns and seed predation in 12 mast-seeding species: Pinus pinea, Astragalus scaphoides, Sorbus aucuparia, Quercus ilex, Q. humilis, Q. rubra, Q. alba, Q. montana, Chionochloa pallens, C. macra, Celmisia lyallii and Phormium tenax.Key resultsFecundity was non-linearly related to masting patterns. Small and unproductive plants frequently failed to produce any seeds, which elevated their annual variation and decreased synchrony. Above a low fecundity threshold, plants had similar variability and synchrony, regardless of their size and productivity.ConclusionsOur study shows that within-species variation in masting patterns is correlated with variation in fecundity, which in turn is related to plant size. Low synchrony of low-fertility plants shows that the failure years were idiosyncratic to each small plant, which in turn implies that the small plants fail to reproduce because of plant-specific factors (e.g. internal resource limits). Thus, the behaviour of these sub-producers is apparently the result of trade-offs in resource allocation and environmental limits with which the small plants cannot cope. Plant size and especially fecundity and propensity for mast failure years play a major role in determining the variability and synchrony of reproduction in plants.

Published
2020

17. Moving Sea Ice Prediction Forward via Community Intercomparison

Author

Steele, Michael, Eicken, Hajo, Bhatt, Uma, Bieniek, Peter, Blanchard-Wrigglesworth, Ed, Wiggins, Helen, Turner-Bogren, Betsy, Hamilton, Lawrence, Little, Joseph, Massonnet, François, Meier, Walter N., Overland, James, Serreze, Mark, Stroeve, Julienne, Walsh, John, and Wang, Muyin

Published
2021

19. Learning about New Demands in Schools: Considering Algebra Policy Environments (LANDSCAPE). CPRE Research Reports

Author

University of Pennsylvania, Consortium for Policy Research in Education (CPRE), Steele, Michael D., Remillard, Janine, Baker, John Y., Keazer, Lindsay M., and Herbel-Eisenmann, Beth

Abstract

The past three decades in mathematics education policy and research have seen a considerable focus on algebra and its place in secondary schools. Access to and success in the first high school course, most often termed Algebra I, has been framed as a civil rights issue, a harbinger of college success, and a lynchpin to global competitiveness. Policymakers have targeted access to Algebra I through universal enrollment policies at specific grade levels, while educational researchers and policy analysts have investigated the efficacy of such policies in improving student outcomes. [This document is a reissue of the April 2016 CPRE Research Report RR-86 under the same title.]

Published
2016

29. Salinity and Stratification at the Sea Ice Edge (SASSIE): an oceanographic field campaign in the Beaufort Sea.

Author

Drushka, Kyla, Westbrook, Elizabeth, Bingham, Frederick M., Gaube, Peter, Dickinson, Suzanne, Fournier, Severine, Menezes, Viviane, Misra, Sidharth, Pérez Valentín, Jaynice, Rainville, Edwin J., Schanze, Julian J., Schmidgall, Carlyn, Shcherbina, Andrey, Steele, Michael, Thomson, Jim, and Zippel, Seth

Subjects
HALOCLINE, ENTHALPY, CLIMATE feedbacks, AUTUMN, METEOROLOGY, SEAWATER salinity
Abstract

As our planet warms, Arctic sea ice coverage continues to decline, resulting in complex feedbacks with the climate system. The core objective of NASA's Salinity and Stratification at the Sea Ice Edge (SASSIE) mission is to understand how ocean salinity and near-surface stratification affect upper-ocean heat content and thus sea ice freeze and melt. SASSIE specifically focuses on the formation of Arctic Sea ice in autumn. The SASSIE field campaign in 2022 collected detailed observations of upper-ocean properties and meteorology near the sea ice edge in the Beaufort Sea using ship-based and piloted and drifting assets. The observations collected during SASSIE include vertical profiles of stratification up to the sea surface, air–sea fluxes, and ancillary measurements that are being used to better understand the role of salinity in coupled Arctic air–sea–ice processes. This publication provides a detailed overview of the activities during the 2022 SASSIE campaign and presents the publicly available datasets generated by this mission (available at https://podaac.jpl.nasa.gov/SASSIE , last access: 29 May 2024; DOIs for individual datasets in the "Data availability" section), introducing an accompanying repository that highlights the numerical routines used to generate the figures shown in this work. [ABSTRACT FROM AUTHOR]

Published
2024
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37. Persister cells in Burkholderia thailandensis

Author

Steele, Michael Edward George, Titball, Richard, Hemsley, Claudia, and Atkins, Helen

Subjects
615.3, Persister cells, Burkholderia thailandensis, Antibiotic tolerance
Abstract

Persister cells are able to survive in the presence of high concentrations of antibiotic, and re-grow once the antibiotic has been removed. Unlike conventional antibiotic resistance, the antibiotic tolerance of persister cells is due to phenotypic switching, and is non-inherited. There is growing evidence for a role of persisters in various persistent bacterial diseases. Burkholderia pseudomallei is a pathogen which causes melioidosis, which often persists in the host despite antibiotic treatment. As persister cells may contribute to persistent melioidosis, this study investigated persisters in B. thailandensis, as a model for B. pseudomallei. Treatment of B. thailandensis with ceftazidime, ciprofloxacin, imipenem or trimethoprim demonstrated persister cells which survived antibiotic treatment. Persister frequencies were increased in the absence of oxygen, and higher in stationary phase cultures compared with growing cultures. Drug concentration did not affect persister frequencies, and inherited antibiotic resistance was not detected. Different persister fractions were detected using treatment with multiple antibiotics, indicating heterogeneous susceptibility to antibiotics. In order to increase understanding of the molecular basis of B. thailandensis persister cells, a transposon mutagenesis-based sequencing approach was used on persister cultures. This indicated some issues with genome coverage and mutant diversity. Genes were identified from mutants present before and/or after ciprofloxacin treatment. In order to try to eradicate persister cells from a culture, two anti-persister strategies were tested. Itaconate appeared to stimulate growth of B. thailandensis, increasing susceptibility to the antibiotic ceftazidime. However, the overall effect of the combination was no greater than ceftazidime alone in the conditions tested. Metronidazole was effective against a persister culture under anaerobic conditions, suggesting it may be useful in treating anaerobic persisters. Treatment of B. pseudomallei infected mice with metronidazole and ceftazidime did not improve survival over ceftazidime treatment alone.

Published
2016

38. Teacher Positioning and Agency to Act: Talking about 'Low-Level' Students

Author

Suh, Heejoo, Musselman, Alexandria Theakston, Herbel-Eisenmann, Beth, and Steele, Michael D.

Abstract

In this paper, we share our dilemma of disrupting teachers' deficit frames of students. The data comes from a professional development program with nine secondary mathematics teachers. In particular, we attended to when teachers talk about "low-level" students. Drawing on Harré and van Langenhove's (1999) idea of positioning, we examined teachers' self positioning and their associated storylines. By noticing and attending to positionings and storylines in professional development, we suggest, mathematics teacher educators can consider how to disrupt these deficit frames by recasting positionings and storylines. [For the complete proceedings, see ED584443.]

Published
2013

39. Predicting September Arctic Sea Ice: A Multi-Model Seasonal Skill Comparison

Author

Bushuk, Mitchell, Ali, Sahara, Bailey, David A, Bao, Qing, Batté, Lauriane, Bhatt, Uma S, Blanchard-Wrigglesworth, Edward, Blockley, Ed, Cawley, Gavin, Chi, Junhwa, Counillon, François, Coulombe, Philippe Goulet, Cullather, Richard I, Diebold, Francis X, Dirkson, Arlan, Exarchou, Eleftheria, Göbel, Maximilian, Gregory, William, Guemas, Virginie, Hamilton, Lawrence, He, Bian, Horvath, Sean, Ionita, Monica, Kay, Jennifer E, Kim, Eliot, Kimura, Noriaki, Kondrashov, Dmitri, Labe, Zachary M, Lee, WooSung, Lee, Younjoo J, Li, Cuihua, Li, Xuewei, Lin, Yongcheng, Liu, Yanyun, Maslowski, Wieslaw, Massonnet, François, Meier, Walter N, Merryfield, William J, Myint, Hannah, Navarro, Juan C Acosta, Petty, Alek, Qiao, Fangli, Schröder, David, Schweiger, Axel, Shu, Qi, Sigmond, Michael, Steele, Michael, Stroeve, Julienne, Sun, Nico, Tietsche, Steffen, Tsamados, Michel, Wang, Keguang, Wang, Jianwu, Wang, Wanqiu, Wang, Yiguo, Wang, Yun, Williams, James, Yang, Qinghua, Yuan, Xiaojun, Zhang, Jinlun, Zhang, Yongfei, Bushuk, Mitchell, Ali, Sahara, Bailey, David A, Bao, Qing, Batté, Lauriane, Bhatt, Uma S, Blanchard-Wrigglesworth, Edward, Blockley, Ed, Cawley, Gavin, Chi, Junhwa, Counillon, François, Coulombe, Philippe Goulet, Cullather, Richard I, Diebold, Francis X, Dirkson, Arlan, Exarchou, Eleftheria, Göbel, Maximilian, Gregory, William, Guemas, Virginie, Hamilton, Lawrence, He, Bian, Horvath, Sean, Ionita, Monica, Kay, Jennifer E, Kim, Eliot, Kimura, Noriaki, Kondrashov, Dmitri, Labe, Zachary M, Lee, WooSung, Lee, Younjoo J, Li, Cuihua, Li, Xuewei, Lin, Yongcheng, Liu, Yanyun, Maslowski, Wieslaw, Massonnet, François, Meier, Walter N, Merryfield, William J, Myint, Hannah, Navarro, Juan C Acosta, Petty, Alek, Qiao, Fangli, Schröder, David, Schweiger, Axel, Shu, Qi, Sigmond, Michael, Steele, Michael, Stroeve, Julienne, Sun, Nico, Tietsche, Steffen, Tsamados, Michel, Wang, Keguang, Wang, Jianwu, Wang, Wanqiu, Wang, Yiguo, Wang, Yun, Williams, James, Yang, Qinghua, Yuan, Xiaojun, Zhang, Jinlun, and Zhang, Yongfei

Abstract

Abstract This study quantifies the state-of-the-art in the rapidly growing field of seasonal Arctic sea ice prediction. A novel multi-model dataset of retrospective seasonal predictions of September Arctic sea ice is created and analyzed, consisting of community contributions from 17 statistical models and 17 dynamical models. Prediction skill is compared over the period 2001–2020 for predictions of Pan-Arctic sea ice extent (SIE), regional SIE, and local sea ice concentration (SIC) initialized on June 1, July 1, August 1, and September 1. This diverse set of statistical and dynamical models can individually predict linearly detrended Pan-Arctic SIE anomalies with skill, and a multi-model median prediction has correlation coefficients of 0.79, 0.86, 0.92, and 0.99 at these respective initialization times. Regional SIE predictions have similar skill to Pan-Arctic predictions in the Alaskan and Siberian regions, whereas regional skill is lower in the Canadian, Atlantic, and Central Arctic sectors. The skill of dynamical and statistical models is generally comparable for Pan-Arctic SIE, whereas dynamical models outperform their statistical counterparts for regional and local predictions. The prediction systems are found to provide the most value added relative to basic reference forecasts in the extreme SIE years of 1996, 2007, and 2012. SIE prediction errors do not show clear trends over time, suggesting that there has been minimal change in inherent sea ice predictability over the satellite era. Overall, this study demonstrates that there are bright prospects for skillful operational predictions of September sea ice at least three months in advance.

Published
2024

40. A global initiative for ecological and evolutionary hologenomics

Author

Leonard, Aoife, Abalos, Javier, Adhola, Titus, Aguirre, Windsor, Aizpurua, Ostaizka, Ali, Shahzad, Andreone, Franco, Aubret, Fabien, Ávila-Palma, Hefer D., Alcantara, Lizbeth Fabiola Bautista, Beltrán, Juan F., Berg, Rachel, Berg, Thomas Bjørneboe, Bertolino, Sandro, Blumstein, Daniel T., Boldgiv, Bazartseren, Borowski, Zbigniew, Boubli, Jean Philippe, Büchner, Sven, Cabido, Carlos, Camacho, Carlos, Chaparro, Juan C., Charmantier, Anne, D'Elía, Guillermo, da Silva, Luis P., Dalsgaard, Bo, de Franceschi, Christophe, de la Cruz, Ferran, de la Sancha, Noé U., Denoël, Mathieu, Eisenhofer, Raphael, Feiner, Nathalie, Fernandes, Joana M., Figuerola, Jordi, Fusani, Leonida, Gangoso, Laura, García-Roa, Roberto, Gasperini, Stefania, Gaun, Nanna, Thomas, M., Gilbert, P., Gomez-Mestre, Ivan, Graves, Gary R., Groombridge, Jim J., Hardouin, Emilie A., Hernández, Mauricio, Herrera M., L. Gerardo, Hodder, Kathy, Hosner, Peter A., Hurtado, Natali, Juste, Javier, Knowles, Sarah C.L., Kohl, Kevin D., Korine, Carmi, Kornilev, Yurii V., Kramer-Schadt, Stephanie, Lambin, Xavier, Lattenkamp, Ella Z., Lauritsen, Jonas, Li, Guoliang, López, Celeste María, Baucells, Adrià López, Cohen, Tali Magory, Manzo, Emiliano, Marteau, Mélanie, Martin, Lynn B., Bideguren, Garazi Martin, Mazzamuto, Maria Vittoria, Monadjem, Ara, Nietlisbach, Pirmin, Øksnebjerg, Daniel Bilyeli, Packer, Jasmin G., Pepke, Michael L., Peralta-Sánchez, Juan M., Perdomo, Adrián, de Lanuza, Guillem Pérez i, Pietroni, Carlotta, Poyet, Mathilde, Rahbek, Carsten, Ramaraj, Thiruvarangan, Caldas, Yuliaxis Ramayo, Razgour, Orly, Rebelo, Hugo, Reif, Jiří, Rimbach, Rebecca, Rocha, Ricardo, Rocha, Rita G., Fernandes, Carlos Rodríguez, Romeo, Claudia, Ruuskanen, Suvi, Sakaluk, Scott K., Santicchia, Francesca, Sarraude, Tom, Sørås, Rune, Spada, Martina, Steele, Michael A., Stothart, Mason R., Sunje, Emina, Sutton, Alex O., Szulkin, Marta, Takahata, Yu, Thompson, Charles F., Thorup, Kasper, Tomazetto, Geizecler, Torrent, Laura, Toshkova, Nia, Tranquillo, Claudia, Turcios-Casco, Manfredo Alejandro, Uller, Tobias, van Riemsdijk, Isolde, Velo-Antón, Guillermo, Verbeylen, Goedele, Videvall, Elin, Voigt, Christian C., Wauters, Lucas A., Wellenreuther, Maren, Yanchukov, Alexey, Alberdi, Antton, Leonard, Aoife, Abalos, Javier, Adhola, Titus, Aguirre, Windsor, Aizpurua, Ostaizka, Ali, Shahzad, Andreone, Franco, Aubret, Fabien, Ávila-Palma, Hefer D., Alcantara, Lizbeth Fabiola Bautista, Beltrán, Juan F., Berg, Rachel, Berg, Thomas Bjørneboe, Bertolino, Sandro, Blumstein, Daniel T., Boldgiv, Bazartseren, Borowski, Zbigniew, Boubli, Jean Philippe, Büchner, Sven, Cabido, Carlos, Camacho, Carlos, Chaparro, Juan C., Charmantier, Anne, D'Elía, Guillermo, da Silva, Luis P., Dalsgaard, Bo, de Franceschi, Christophe, de la Cruz, Ferran, de la Sancha, Noé U., Denoël, Mathieu, Eisenhofer, Raphael, Feiner, Nathalie, Fernandes, Joana M., Figuerola, Jordi, Fusani, Leonida, Gangoso, Laura, García-Roa, Roberto, Gasperini, Stefania, Gaun, Nanna, Thomas, M., Gilbert, P., Gomez-Mestre, Ivan, Graves, Gary R., Groombridge, Jim J., Hardouin, Emilie A., Hernández, Mauricio, Herrera M., L. Gerardo, Hodder, Kathy, Hosner, Peter A., Hurtado, Natali, Juste, Javier, Knowles, Sarah C.L., Kohl, Kevin D., Korine, Carmi, Kornilev, Yurii V., Kramer-Schadt, Stephanie, Lambin, Xavier, Lattenkamp, Ella Z., Lauritsen, Jonas, Li, Guoliang, López, Celeste María, Baucells, Adrià López, Cohen, Tali Magory, Manzo, Emiliano, Marteau, Mélanie, Martin, Lynn B., Bideguren, Garazi Martin, Mazzamuto, Maria Vittoria, Monadjem, Ara, Nietlisbach, Pirmin, Øksnebjerg, Daniel Bilyeli, Packer, Jasmin G., Pepke, Michael L., Peralta-Sánchez, Juan M., Perdomo, Adrián, de Lanuza, Guillem Pérez i, Pietroni, Carlotta, Poyet, Mathilde, Rahbek, Carsten, Ramaraj, Thiruvarangan, Caldas, Yuliaxis Ramayo, Razgour, Orly, Rebelo, Hugo, Reif, Jiří, Rimbach, Rebecca, Rocha, Ricardo, Rocha, Rita G., Fernandes, Carlos Rodríguez, Romeo, Claudia, Ruuskanen, Suvi, Sakaluk, Scott K., Santicchia, Francesca, Sarraude, Tom, Sørås, Rune, Spada, Martina, Steele, Michael A., Stothart, Mason R., Sunje, Emina, Sutton, Alex O., Szulkin, Marta, Takahata, Yu, Thompson, Charles F., Thorup, Kasper, Tomazetto, Geizecler, Torrent, Laura, Toshkova, Nia, Tranquillo, Claudia, Turcios-Casco, Manfredo Alejandro, Uller, Tobias, van Riemsdijk, Isolde, Velo-Antón, Guillermo, Verbeylen, Goedele, Videvall, Elin, Voigt, Christian C., Wauters, Lucas A., Wellenreuther, Maren, Yanchukov, Alexey, and Alberdi, Antton

Abstract

The Earth Hologenome Initiative (EHI) is a global collaboration to generate and analyse hologenomic data from wild animals and associated microorganisms using standardised methodologies underpinned by open and inclusive research principles. Initially focused on vertebrates, it aims to re-examine ecological and evolutionary questions by studying host–microbiota interactions from a systemic perspective.

Published
2024

43. Author Correction: Continent-wide tree fecundity driven by indirect climate effects

Author

Clark, James S., Andrus, Robert, Aubry-Kientz, Melaine, Bergeron, Yves, Bogdziewicz, Michal, Bragg, Don C., Brockway, Dale, Cleavitt, Natalie L., Cohen, Susan, Courbaud, Benoit, Daley, Robert, Das, Adrian J., Dietze, Michael, Fahey, Timothy J., Fer, Istem, Franklin, Jerry F., Gehring, Catherine A., Gilbert, Gregory S., Greenberg, Cathryn H., Guo, Qinfeng, HilleRisLambers, Janneke, Ibanez, Ines, Johnstone, Jill, Kilner, Christopher L., Knops, Johannes, Koenig, Walter D., Kunstler, Georges, LaMontagne, Jalene M., Legg, Kristin L., Luongo, Jordan, Lutz, James A., Macias, Diana, McIntire, Eliot J. B., Messaoud, Yassine, Moore, Christopher M., Moran, Emily, Myers, Jonathan A., Myers, Orrin B., Nunez, Chase, Parmenter, Robert, Pearse, Sam, Pearson, Scott, Poulton-Kamakura, Renata, Ready, Ethan, Redmond, Miranda D., Reid, Chantal D., Rodman, Kyle C., Scher, C. Lane, Schlesinger, William H., Schwantes, Amanda M., Shanahan, Erin, Sharma, Shubhi, Steele, Michael A., Stephenson, Nathan L., Sutton, Samantha, Swenson, Jennifer J., Swift, Margaret, Veblen, Thomas T., Whipple, Amy V., Whitham, Thomas G., Wion, Andreas P., Zhu, Kai, and Zlotin, Roman

Published
2021
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46. Measuring Reading Comprehension and Mathematics Instruction in Urban Middle Schools: A Pilot Study of the Instructional Quality Assessment. CSE Technical Report 681

Author

National Center for Research on Evaluation, Standards, and Student Testing, Los Angeles, CA., Matsumura, Lindsay Clare, Slater, Sharon Cadman, Junker, Brian, Peterson, Maureen, Boston, Melissa, Steele, Michael, and Resnick, Lauren

Abstract

The quality of reading comprehension and mathematics instruction was explored in five urban middle schools using the Instructional Quality Assessment (IQA) toolkit (N = 34 teachers). The IQA is comprised of protocols for rating observed instruction and the quality of teachers' assignments with student work. The purpose of this research was to investigate the reliability and potential validity of the ratings of these data sources. Commensurate with other research on the quality of middle schools, our results indicated that the quality of instruction varied a great deal within schools and was of a "basic" quality overall. Results indicated a moderate to high level of reliability. Four assignments with student work yielded a stable estimate of quality in both content areas, and when teachers complied with the requirements of the research as few as two observations yielded a stable estimate of teaching quality in both content areas as well. The quality of teachers' observations and assignments were significantly associated in mathematics, but not in reading comprehension. Because of the small sample size it was not possible to apply multi-level models. The relation between the IQA and student achievement on the SAT-10 was explored using linear regression techniques. Results indicated that after controlling for students' prior achievement, socio-economic status (SES), ethnicity, language, and IEP status, the IQA assignment measure in reading comprehension predicted student achievement on the Total Reading, Reading Comprehension, and Vocabulary subscores of the SAT-10. The observation measure in reading comprehension predicted student outcomes on the Reading Comprehension subscore of the SAT-10 only. In mathematics, the quality of teachers' assignments predicted students' achievement on the Procedures subscore of the SAT-10. The quality of observed instruction in mathematics predicted students' achievement on the Procedures and Total Math subscores. Without accounting for clustering within classrooms and schools as multilevel models do, our linear regression analyses may lead to results that appear stronger than they actually are. Nevertheless our analyses indicate the direction of trend in these relationships and raise important questions regarding which data sources may be best (classroom assignments or observations) for measuring specific aspects of instruction and student outcomes. Additional research with larger samples of teachers is needed to make definitive conclusions about the validity of the IQA ratings and under what conditions one might choose to either observe in classrooms or collect assignments with student work. The following are appended: (1) IQA Rubrics; and (2) High and Low Quality Examples of Observed Lessons and Assignments. (Contains 21 tables and 9 footnotes.)

Published
2006

49. Simulated Power of Some Discrete Goodness-of-Fit Test Statistics For Testing the Null Hypothesis of a Zig-Zag Distribution

Author

Ampadu, Clement, Wang, Daniel, and Steele, Michael

Subjects
Mathematics - Statistics Theory, Primary 62G30, Secondary 62G10
Abstract

In this paper, we compare the powers of several discrete goodness-of-fit test statistics considered by Steele and Chaseling [10] under the null hypothesis of a 'zig-zag' distribution. The results suggest that the Discrete Kolmogorov-Smirnov test statistic is generally more powerful for the decreasing trend alternative. The Pearson Chi-Square statistic is generally more powerful for the increasing, unimodal, leptokurtic, platykurtic and bath-tub shaped alternatives. Finally, both the Nominal Kolmogorov- Smirnov and the Pearson Chi-Square test statistic are generally more powerful for the bimodal alternative. We also address the issue of the sensitivity of the test statistics to the alternatives under the 'zig-zag' null. In comparison to the uniform null of Steele and Chaseling [10], our investigation shows that the Discrete KS test statistic is most sensitive to the decreasing trend alternative; the Pearson Chi-Square statistic is most sensitive to both the leptokurtic and platykurtic trend alternatives. In particular, under the 'zig-zag' null we are able to clearly identify the most powerful test statistic for the platykurtic and leptokurtic alternatives, compared to the uniform null of Steele and Chaseling [10], which could not make such identification., Comment: 15 pages, 7 figures, 3 tables

Published
2010

50. Validation and Application of Satellite-Derived Sea Surface Temperature Gradients in the Bering Strait and Bering Sea.

Author

Vazquez-Cuervo, Jorge, Steele, Michael, Wethey, David S., Gómez-Valdés, José, García-Reyes, Marisol, Spratt, Rachel, and Wang, Yang

Subjects
*REMOTE sensing, *SEA ice, *MICROWAVE remote sensing, *EXTREME weather, *ROOT-mean-squares
Abstract

The Arctic is one of the most important regions in the world's oceans for understanding the impacts of a changing climate. Yet, it is also difficult to measure because of extreme weather and ice conditions. In this work, we directly compare four datasets from the Group for High-Resolution Sea Surface Temperature (GHRSST) with a NASA Saildrone deployment along the Alaskan Coast and the Bering Sea and Bering Strait. The four datasets used are the Remote Sensing Systems Microwave Infrared Optimally Interpolated (MWIR) product, the Canadian Meteorological Center (CMC) product, the Daily Optimally Interpolated Product (DOISST), and the Operational Sea Surface Temperature and Ice Analysis (OSTIA) product. Spatial sea surface temperature (SST) gradients were derived for both the Saildrone deployment and GHRSST products, with the GHRSST products collocated with the Saildrone deployment. Overall, statistics indicate that the OSTIA product had a correlation of 0.79 and a root mean square difference of 0.11 °C/km when compared with Saildrone. CMC had the highest correlation of 0.81. Scatter plots indicate that OSTIA had the slope closest to one, thus best reproducing the magnitudes of the Saildrone gradients. Differences increased at latitudes > 65°N where sea ice would have a greater impact. A trend analysis was then performed on the gradient fields. Overall, positive trends in gradients occurred in areas along the coastal regions. A negative trend occurred at approximately 60°N. A major finding of this study is that future work needs to revolve around the impact of changing ice conditions on SST gradients. Another major finding is that a northward shift in the southern ice edge occurred after 2010 with a maxima at approximately 2019. This indicates that the shift of the southern ice edge is not gradual but has dramatically increased over the last decade. Future work needs to revolve around examining the possible causes for this northward shift. [ABSTRACT FROM AUTHOR]

Published
2024
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